External Bus Interface (EBI)
MPC5565 Microcontroller Reference Manual, Rev. 1.0
Freescale Semiconductor
12-5
•
Bus monitor
— User selectable
— Programmable timeout period (with 8 external bus clock resolution)
•
Port size configuration per chip select (16 or 32 bits)
•
Port size for calibration chip select is 16 bits
•
Configurable wait states (via chip selects)
•
Four chip select (CS[0:3]) signals
•
Support for dynamic calibration with up to three calibration chip selects
(CAL_CS[0] and CAL_CS[2:3]),
•
Write/byte enable (WE/BE) signals depend on the package: 324 BGA: two signals (WE/BE[0:1])
•
Configurable bus speed modes (1/2 or 1/4 of system clock frequency)
•
Module disable modes for power savings
•
Optional automatic CLKOUT gating to save power and reduce EMI
•
Compatible with MPC5xx external bus
Refer to
Section 12.4.1.18, “Compatible with MPC5xx External Bus (with Some Limitations)
.”
12.1.4
Modes of Operation
The mode of the EBI is determined by the MDIS and EXTM bits in the EBI_MCR. Refer to
Section 12.3.1.3, “EBI Module Configuration Register (EBI_MCR)
” for details. Configurable bus speed
modes and debug mode are modes that the MCU can enter, in parallel to the EBI being configured in one
of its module-specific modes.
12.1.4.1
Single Master Mode
In single master mode, the EBI responds to internal requests matching one of its regions, but ignores all
externally-initiated bus requests. The MCU is the only master allowed to initiate transactions on the
external bus in this mode; therefore, it acts as a parked master and does not have to arbitrate for the bus
before starting each cycle. Single master mode is entered when EXTM = 0 and MDIS = 0 in the
EBI_MCR.
NOTE
The MPC5565 does not include arbitration signals BR, BG, and BB.
12.1.4.2
External Master Mode
When the MCU is in external master mode, the EBI responds to internal requests matching one of its
regions, and also to external master accesses to internal address space. External master mode is entered
when EXTM = 1 and MDIS = 0 in the EBI_MCR register.
Because the MPC5565 does not have arbitration, the dual-master operation (multiple masters initiating
external bus cycles) is not supported. A multi-MCU system with one master and one slave is supported.
Summary of Contents for MPC5565
Page 18: ...MPC5565 Microcontroller Reference Manual Devices Supported MPC5565 MPC5565 RM Rev 1 0 09 2007...
Page 34: ...MPC5565 Reference Manual Rev 1 0 Freescale Semiconductor 15...
Page 35: ...MPC5565 Reference Manual Rev 1 0 16 Freescale Semiconductor...
Page 553: ...Flash Memory MPC5565 Microcontroller Reference Manual Rev 1 0 13 38 Freescale Semiconductor...
Page 559: ...SRAM MPC5565 Microcontroller Reference Manual Rev 1 0 14 6 Freescale Semiconductor...
Page 973: ...Preface MPC5565 Microcontroller Reference Manual Rev 1 0 21 36 Freescale Semiconductor...
Page 1153: ...Calibration MPC5565 Microcontroller Reference Manual Rev 1 0 B 8 Freescale Semiconductor...